4. Skull (Wright) Flashcards
What make up our axial skeleton?
- 1. Skull
- 2. Vertebral column
- 3. Thoracic cage
What makes up our appendicular skeleton?
1. Upper and lower limbs
2. Pectoral/pelvic girdles
What are the 8 cranial bones?
- Parietal (2 because paired)
- Temporal (2 because paired)
- Frontal
- Occipital
- Sphenoid
- Ethmoid
What are the 14 facial bones?
- Zygomatic (2 because paired)
- Lacrimal (2 because paired)
- Nasal (2 because paired)
- Palatine (2 because paired)
- Maxillae (2 because paired)
- Inferior nasal conchae (2 because paired)
- Vomer
- Mandible
Craniometric landmarks
- Pterion
- Lambda
- Glabella
- Nasion
- Akanthion
- Inion
- Pogonion
- Pterion-> where frontal, parietal, temporal and sphenoid bone meet. Middle meningeal A runs through it.
- Lambda-> intersection of sagittal and lamboid sutures and location of posterior fontanelle.
- Glabella -> area superior to nasion between supraorbital tori/
- Nasion -> intersection of two nasal bones and frontal
- Akanthion-> where nasal prominence comes out
- Inion-> occipital protuberance
- Pogonion- tip of chin
Damage to the pterion can damage what?
Middle meningeal A.
We lacked ______ in primitive species. However, they since have appeared and enlarged during skull evolution.
Fenestrae - holes that open and connect with the orbit of the eye.
How has neurocranium evolved over time? (?)
Maintained fetal form of skull in adulthood
Where does the frontal bone meet the parietal bone?
Coronal suture
Bulging over eyes on exterior skull is called
superciliary arch
What is a midline remnant of the fused frontal bones?
can result in?
Metopic sutures; can result in cleft lip
What part of skill do you get the terminal branching of V1 (supraorbital N) arising and vessels, which provides sensation to the skin on the forehead?
Supraorbital notch/foramen
What is the frontal crest?
Attachment site for falx cerebri, which is protective connective tissue for the brain.
Located: internal surface of frontal bone.
PARIETAL BONE
What is the articulation between the two parietal bones?
Sagittal sutures
Where occipital bone meets parietal bone
Lambdoidal Suture
Where parietal bone meets temporal bone
Squamosal suture
CN: surgical access to cranial cavity: bone flaps
how can we improve healing?
Surgeons access the cranial cavity and brain by performing a craniotomy, where a section of the neurocranium, called a bone flap, is elevated or removed. Bone flaps are put back into place with wire or metal plates.
Healing is best when flap has overlaying muscle and skin, so that it retains its own blood supply during the procedure and after repositioning.
If the bone flap is not replaced (i.e., a permanent plastic or metal plate replaces the flap), the procedure is called a
cranioectomy
How can we age bones?
- By looking at sutures.
- As we age, lines fuse and obliterate.
- Beginning at 30-40 years old-> internal surface obliterate
- 10 years later-> external surgace obliterates
Obliteration of sutures usually begins at the _____ and continues sequentially in the _____, _____, and _____ sutures. Closure times vary considerably.
Obliteration of sutures usually begins at the bregma and continues sequentially in the sagittal, coronal, and lambdoid sutures. Closure times vary considerably.
What houses the middle ear and is important for hearing and balance and CNS?
TEMPORAL BONE
Houses facial N and branches.
Important things on external surface of temporal bone
- Zygomatic process
- Mastoid process
- Styloid process
- Mandibular fossa
- External auditory meatus
Important things on interior surface of temporal bone
- Groove for sigmoid venous sinus
- Internal acoustic meatus-> CN 7 and 8 run through it.
- Petrous portion- hard part of temporal bone that protects inner ear
What is a passageway for
1. medulla oblongata
2. accessory nerve
3. vertebral as.
Foramen magnum
___________ enters the foramen magnum and exits the jugular foramen.
Spinal accessory n.
Where does C1 articulate with skull?
Occipital condyles